JP2000055637A - Work inspecting device, part image generating device, work inspecting method, and computor-readable storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily cope with a work supplied newly as an inspecting object. SOLUTION: In this inspecting method, a total image of a work to detected newly in on-line inspection to conduct teaching is retrieved using plural part template images preliminerily prepared, the template image having the highest correlation is selected as the result of the retrieval(S21-S22), an image area within the total image of the work corresponding to an area arranged with the template image is extracted, and the extracted template image is correlated with a work ID (identifying information) of the work (S23-S24). Work inspection is continued in a system in an on-line inspection side adding the correlated template image and the work ID.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work inspecting apparatus, a part image generating apparatus, a work inspecting method, and a computer-readable storage medium for inspecting the quality of a work. The present invention relates to a work inspection device, a component image generation device, a work inspection method, and a computer-readable storage medium suitable for use in a process.

[0002]

2. Description of the Related Art Conventionally, in an assembly line for mass-produced products, an image processing technique has been employed for inspecting an assembled work. As an example of such a technique, for example, Japanese Patent Laid-Open No. 9-101123 is disclosed. The image of the engine bracket attached to the engine housing in the previous process is imaged from a predetermined direction, and the quality of the engine bracket is determined based on the result of comparing the characteristic amount of the imaged image with a predetermined reference value. A method of making a decision has been proposed.

[0003]

However, using the conventional inspection method utilizing the above-described image processing technology, the quality of a work (a work with parts attached) is automatically judged on an inspection line. Prior to the start of the automatic inspection on the inspection line, all types of works to be inspected (works as non-defective products) are prepared in advance, and based on image data obtained by individually imaging these works,
It is necessary to prepare a reference value (reference data) for quality judgment of each work. Therefore, when the above-described inspection method is employed, particularly when employed in an inspection process of an assembly line that performs a so-called mixed flow of various types, the length of the lead time until the start of operation by the automatic inspection of the inspection process is reduced. It becomes a problem. Further, when a new model is to be inspected after the start of the automatic inspection, the entire assembly line must be stopped to cope with the problem, and the production efficiency is degraded due to the stop of the line.

Accordingly, an object of the present invention is to provide a work inspection apparatus, a component image generation apparatus, a work inspection method, and a computer-readable storage medium which can easily cope with a work to be newly inspected.

[0005]

In order to achieve the above object, a work inspection apparatus according to the present invention has the following configuration.

That is, inspection means for inspecting the quality of a work to be inspected based on an entire image of the work to be inspected and a plurality of component images indicating the state of components assembled on the work prepared in advance. A workpiece inspection apparatus having a component image corresponding to a workpiece to be inspected this time, when the component image corresponding to the workpiece is not prepared, by searching the entire image of the workpiece, the correlation is highest among the plurality of component images. Selecting means for selecting a part image, and extracting means for extracting an image area corresponding to the part image selected by the selecting means from the entire image of the work to be inspected as a part image corresponding to the work. It is characterized by having.

Further, for example, in the work inspection apparatus, the component image generation by the component image generation means can be executed at an independent timing different from a plurality of work inspections by the inspection means.

Further, in order to achieve the above object, a component image generating apparatus according to the present invention has the following configuration.

That is, there is provided a component image generating apparatus for generating a component image indicating a state of a component mounted on a workpiece,
Selecting means for selecting the most correlated component image from among a plurality of component images indicating the state of the component assembled to the work prepared in advance by searching the entire image of the target work; and Extracting means for extracting an image area corresponding to the selected part image from the entire image of the work as a part image corresponding to the work;
It is characterized by having.

In order to achieve the above object, a work inspection method according to the present invention has the following features.

That is, a work inspection for inspecting the acceptability of a work to be inspected based on an entire image of the work to be inspected and a plurality of component images indicating a state of parts assembled to the work prepared in advance. Selecting a component image having the highest correlation from the plurality of component images by searching the entire image of the workpiece when a component image corresponding to the workpiece to be inspected this time is not prepared. And extracting an image area corresponding to the selected component image from the entire image of the workpiece to be inspected as a component image corresponding to the workpiece. The following work inspection is performed using the part image thus obtained.

Further, the present invention is characterized by a computer-readable storage medium for operating a computer as an apparatus for realizing the work inspection apparatus and the component image generation apparatus.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings, applying to an inspection process (inspection line) in a vehicle engine assembly line.

In the present embodiment, on the inspection line, an inspection is performed to determine whether or not a predetermined component is attached to a predetermined position of a plurality of types of engines as works.

First, the overall configuration of the inspection system according to the present embodiment will be described with reference to FIGS.

FIG. 1 is a block diagram showing an overall configuration of an inspection system as one embodiment of the present invention. FIG. 2 is a diagram showing an arrangement of devices in an online inspection / image recording system in an inspection system as one embodiment of the present invention.

FIG. 1 shows a work inspection apparatus according to this embodiment.
As shown in the figure, an online inspection and image recording system,
It consists of an image teaching system.

First, the role of the online inspection / image recording system will be outlined (details will be described later).

The on-line inspection and image recording system performs a general image template inspection for inspecting whether or not a predetermined component is attached to a predetermined position of an engine to be inspected which flows one after another from an assembly line in a previous process. An online inspection that automatically performs inspection using a matching technique (hereinafter, an automatic inspection mode), and prior to the online inspection, a workpiece that is a non-defective product used for an automatic inspection process, that is, a predetermined component is attached to a predetermined position. Of the entire engine (hereinafter, image recording mode).

In the online inspection / image recording system, a work ID reading unit 1 reads information (hereinafter, work ID) for identifying a model of a work 7 (engine) flowing from an assembly line in a previous process from the work. It is. As a method of reading the work ID from each work 7, a general method such as a method using a combination of a barcode and a barcode reader may be adopted.

An inspection line controller 3 controls the operation of the inspection line 10.
(Programmable controller). In addition, the inspection line controller 3 includes the work ID reading unit 1
The received data relating to the work ID is transmitted to a personal computer (hereinafter, PC) 2A as a control device for controlling the online inspection / image recording system.

4A is a CCD (Charge Coupled Device)
Control of a camera 5 having an image sensor such as
An image processing module that performs predetermined image processing described later based on an image signal obtained from the image processing module. Camera 5
A plurality of whole images of the work 7 are arranged so as to be photographable from different positions as shown in FIG. 2, and which camera image to use for inspection may be set in advance in accordance with the work ID. Reference numeral 6A denotes a monitor which is arranged near the inspection line 10 and displays an image taken by the camera 5.

In the automatic inspection mode, the PC 2A receives the work ID obtained via the inspection line controller 3,
Based on the entire image of the work 7 obtained through the image processing module 4A and the pre-registered component template image, a predetermined position of the target work 7 is
An automatic inspection process for inspecting whether a predetermined component is attached is performed. In the image recording mode,
Work ID obtained via inspection line controller 3
When the entire image of the work 7 corresponding to the above is not registered, an image recording process of photographing an image including the entire shape of the work (hereinafter, referred to as a whole work image) is performed (details will be described later).

On the other hand, the image teaching system comprises an image processing module 4B, a monitor 6B, and a PC 2B. Based on the data of the whole image of the work 7 recorded by the online inspection / image recording system, the automatic teaching of the work is performed. A component template image used for processing is generated (details will be described later).

In this embodiment, the image processing modules 4A and 4B are hardware packages. However, it goes without saying that similar functions may be realized by software inside the PCs 2A and 2B.

FIG. 7 is a block diagram of a personal computer as one embodiment of the present invention, and shows the configuration of the PCs 2A and 2B in this embodiment.

In the figure, reference numeral 22 denotes a display such as a CRT,
Reference numeral 23 denotes a keyboard as input means. A ROM 24 stores a boot program and the like. 25 is
This is a RAM for temporarily storing various processing results. A hard disk drive (HDD) 26 stores a program for realizing an automatic inspection process, an image recording process, and the like described later.
D). Reference numeral 27 denotes a communication interface for communicating with an external device such as the inspection line controller 3 via the communication line 30. PC2A and P2
C2B is communicably connected to each other via a communication line 30 by a mutual communication interface 27. And 28
Is a printer that prints processing results and the like. These components are connected via an internal bus 29 and have a CPU
21 is a PC according to the program stored in the storage device 26.
The whole of 2A and 2B is controlled.

In the present embodiment, the recording of the entire image of the work in the image recording mode is performed automatically during, for example, a start-up preparation period of a new inspection line in which a component template image used in the automatic inspection mode is not yet prepared. Prior to starting the online inspection in the inspection mode, the inspection is performed on a plurality of types of works.

Then, from images representing the overall shape of each work having different work IDs (different models) recorded in the image recording mode, a predetermined method attached to a predetermined position of the work by a general method. Extract the part template image including the part and the background around the part,
The work is associated with the work ID. The part template image associated with the work ID is P
It is registered in the storage device 26 of each of C2A and PC2B.

Next, the processing executed by the PC 2A in the image recording mode will be described.

<Image Recording Process> FIG. 3 is a flowchart showing an image recording process according to one embodiment of the present invention. In the image recording mode, the PC 2A performs the following process for each work.

That is, in the figure, step S1: a work ID is obtained via the inspection line controller 3.

Step S2: It is determined whether or not the entire image of the work (work as a non-defective product) corresponding to the work ID obtained in step S1 is already registered in the storage device 26, and YES (registered) If, the process ends.

Step S3: N in the judgment of step S2
If O (unregistered), the entire shape of the work 7 currently present on the inspection line 10 is photographed by the camera 5 and the photographed whole image of the work 7 is recorded in the storage device 26 as a non-defective whole image.

When the operator prepares the component template images of a plurality of works to be inspected for the time being on the inspection line, the operator can shift the PC 2A to the automatic inspection mode and perform the automatic inspection of those works. .

<Automatic Inspection Processing> Next, the processing executed by the PC 2A in the automatic inspection mode will be described.

FIG. 4 is a flowchart showing an automatic inspection process as one embodiment of the present invention. In the automatic inspection mode, the PC 2A performs the following process for each work.

That is, in the figure, step S11: A work ID is obtained via the inspection line controller 3.

Step S12: It is determined whether or not a component template image associated with the obtained work ID exists in the storage device 26.

Steps S16 and S17: If the determination in step S12 is YES (there is a component template image), a component inspection is performed. That is, the entire image of the work 7 currently present on the inspection line 10 is photographed by the camera 5 at the position corresponding to the obtained work ID,
Based on the data of the photographed whole image and the data of the component template image associated with the work ID, whether the template image is present in the photographed whole image by a general template matching method. It is determined whether or not it is (step S16). And
If the determination is YES, the “current inspection line 10
Is a non-defective product in which a predetermined part is attached to a predetermined position in the work existing in the
Ends the automatic inspection process for.

Step S13: If the determination in step S12 is NO (there is no component template image), it is determined whether or not the data of the entire image of the work corresponding to the obtained work ID already exists in the storage device 26.
If YES (there is data for the entire image), step S
Proceed to 18.

Steps S14 and S15: NO in determination in step S13 (no data of entire image)
In this case, the whole image of the work 7 presently present on the inspection line 10 is recorded (preferably, the camera 5 at a different position).
It is needless to say that it is preferable to record a plurality of works using the above-mentioned method), and the image representing the entire shape of the recorded work is associated with the work ID. The whole image of the work obtained in this step and the work ID are used in an image teaching process described later in the PC 2B.

Step S18: If the determination in step S17 is NO (non-defective), and if the determination in step S13 is YES (there is data on the entire image), an alarm is issued to call attention of the operator.

Step S19, Step S20: The operator inspects the work 7 presently present on the inspection line 10 by visual inspection or the like. As a result, when the work is judged to be non-defective, the operator inputs a work payout instruction from an operation panel (not shown). I do. On the other hand, when it is determined that the work needs to be reworked, the need for rework is input from an operation panel (not shown). PC
2A, when a signal indicating a payout instruction is received via the inspection line controller 3 (step S19), or when a signal indicating a need for repair is received (step S19).
20), the automatic inspection process for the work 7 ends.

The work 7 determined to be non-defective in the above-described automatic inspection process is conveyed to a post-process or a reworking process (not shown) under the control of the inspection line controller 3 performed according to an instruction from the PC 2A.

<Image teaching process> Next, PC2B
Will be described with reference to FIGS. 5 and 6. FIG. This processing is for realizing automatic inspection when a work 7 for which a component template image has not been registered is detected in the above-described automatic inspection mode and a work of the same type (model) as the work flows thereafter. The automatic inspection mode in the inspection line 10 is a process executed by the PC 2B while being functionally separated.

FIG. 5 is a view for explaining the image teaching processing as one embodiment of the present invention. Also, FIG.
5 is a flowchart illustrating an image teaching process as one embodiment of the present invention.

In the figure, step S21: the whole image of the work to be taught and the work ID, ie, the work ID, from the PC 2A on the online inspection side via the communication line 30 (or may be obtained via a storage medium). The image data representing the overall shape of the work associated with the work ID by the processing in steps S14 and S15 is read from the PC 2A.

Step S22: Using the plurality of component template images already stored in the storage device 26, the entire image of the work read in step S21 is searched, and as a result, the component template image having the highest correlation is obtained. That is, it is searched whether or not the entire image of the work includes a shape area similar to a plurality of component template images already stored. Is selected, the template image having a high degree of is selected. This selection processing may be performed by image processing such as general edge detection and area extraction based on the density levels of the entire image of the work and the component template image, which are multi-valued gray image data.

Step S23: If any of the component template images already stored are selected and arranged in any of the regions in the entire image of the work by the selection processing in step S22, the template image is displayed. An image area in the entire image of the work corresponding to the arranged area is extracted.

Step S24: The part template image extracted in step S23 and the work ID read in step S21 are registered in the storage device 26 in association with each other. Further, it is preferable to associate the identification information including the identification ID of the camera 5 to be used when inspecting the work in the online inspection. The camera 5 selected at this time is determined, for example, in step S
What is necessary is just to set it as the camera which image | photographed the whole image of the workpiece | work which became the base of the component template image selected in 22. In this case, it is necessary to associate the identification ID of the camera 5 used for shooting with a plurality of component template images registered in advance.

Step S25: The work ID and the component template image associated in step S24 are transferred to the PC 2A on the online inspection side.

By the above-described image teaching processing, a part template image corresponding to a work 7 for which a part template image detected in the automatic inspection mode is not registered can be automatically taught. By using the work ID and the component template image associated by the teaching, the PC 2A automatically determines the quality of the work when the work 7 having the work ID is detected in the subsequent automatic inspection processing. Can be inspected.

In order to realize the automatic teaching, the prerequisite is that when the PC 2A records the entire image of the work such as step S14 in FIG. It is necessary to properly adjust environmental conditions such as adjusting the angle and securing an auxiliary light source for photographing. If this environmental condition cannot be maintained satisfactorily, for example, prior to extracting the component template image from the entire work image in step S23,
The selected state may be displayed on the display 22 or the monitor 6B, and the operator may input whether or not to extract the selected area.

As described above, according to the present embodiment, even if a plurality of workpieces to be inspected on the inspection line 10 cannot all be prepared, if a part template image for a certain type of workpiece can be prepared, the PC 2A
The operation of the automatic inspection of the inspection line 10 can be started. That is, even if an engine of a new model is to be inspected after the operation of the automatic inspection of the inspection line is started, the inspection line 10 is not stopped when the new engine is detected on the inspection line. And the component template image can be taught on the PC2B side. As a result, it is possible to shorten the lead time when starting up the inspection line and to improve the inspection efficiency of the entire inspection line when registering a new type of work (engine) as an inspection target, as compared with the related art.

In this embodiment, PC2A and PC2B
Is provided separately, but is not limited to this.
Needless to say, if there is enough processing capacity of C, two functions may be realized by one unit. If there is still more processing capacity, PC2A can be realized by software for realizing the function of the inspection line controller 3. Needless to say, the controller itself may be operated as the controller and realized by a so-called software PLC.

[0057]

As described above, according to the present invention,
It is possible to provide a work inspection apparatus, a component image generation apparatus, a work inspection method, and a computer-readable storage medium that can easily cope with a work to be newly inspected.

That is, according to the first, sixth to ninth aspects of the present invention, it is possible to easily cope with a new work that has not been inspected until now.

According to the second aspect of the present invention, it is possible to generate a part image corresponding to a work to be newly inspected without interrupting an online work inspection on an inspection line, and to generate the generated part image. By using an image in a work inspection, it is possible to easily cope with a work to be newly inspected.

According to the third aspect of the present invention, the function of inspecting a workpiece and the function of generating a component image corresponding to a workpiece to be newly inspected can be separated.

[0061]

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of an inspection system as one embodiment of the present invention.

FIG. 2 is a diagram showing an arrangement of devices in an online inspection / image recording system in an inspection system as one embodiment of the present invention.

FIG. 3 is a flowchart showing an image recording process as one embodiment of the present invention.

FIG. 4 is a flowchart showing an automatic inspection process as one embodiment of the present invention.

FIG. 5 is a diagram illustrating an image teaching process as one embodiment of the present invention.

FIG. 6 is a flowchart illustrating an image teaching process as one embodiment of the present invention.

FIG. 7 is a block diagram of a personal computer as one embodiment of the present invention.

[Explanation of symbols]

 1: Work ID reading unit, 2A, 2B: Personal computer (PC), 3: Inspection line controller, 4A, 4B: Image processing module, 5: Camera, 6A, 6B: Monitor, 7: Work, 10: Inspection line, 21: CPU, 22: display, 23: keyboard, 24: ROM, 25: RAM, 26: storage device, 27: communication interface, 28: printer, 29: internal bus, 30: communication line,

Continuation of the front page F term (reference) 2F065 AA61 BB05 BB15 BB24 CC11 DD06 FF04 JJ03 JJ05 JJ16 JJ26 NN20 PP15 QQ23 QQ24 QQ25 QQ36 RR08 SS02 SS13 5B057 AA01 CE09 DA03 DB02 DC34 DC39

Claims (9)

[Claims] An inspection means for inspecting the acceptability of a work to be inspected based on an entire image of the work to be inspected and a plurality of component images indicating the states of parts assembled to the work prepared in advance. A workpiece inspection apparatus comprising: when a component image corresponding to a workpiece to be inspected is not prepared this time, by searching the entire image of the workpiece, the correlation is highest among the plurality of component images. Selecting means for selecting a part image; and extracting means for extracting an image area corresponding to the part image selected by the selecting means from the entire image of the work to be inspected as a part image corresponding to the work. A work inspection apparatus, comprising: 2. The workpiece inspection apparatus according to claim 1, wherein the component image generation by the component image generation unit can be executed at an independent timing different from a plurality of workpiece inspections by the inspection unit. Work inspection device as described. 3. The apparatus according to claim 2, wherein said component image generating means and said inspection means are provided separately, and exchange information via communication means or a portable storage medium. Work inspection equipment. 4. The inspection means inspects the acceptability of the work by performing template matching on the entire image of the work to be inspected using the plurality of component images. The work inspection device according to claim 1. 5. In the workpiece inspection apparatus, the plurality of component images are associated with identification information of a workpiece corresponding to the component image, and identification information obtaining means for obtaining identification information of a workpiece to be inspected this time is provided. The work inspection apparatus according to claim 1, further comprising: the selection unit determines whether or not a part image corresponding to the work to be inspected this time is prepared, using the work identification information as a key. 6. A component image generating apparatus for generating a component image indicating a state of a component assembled on a workpiece, wherein the component image is searched for an entire image of a target workpiece, thereby obtaining a component assembled on a previously prepared workpiece. Selecting means for selecting a component image having the highest correlation from a plurality of component images indicating the state of the image, and an image area corresponding to the component image selected by the selecting means, from the entire image of the workpiece to the workpiece. A component image generating apparatus, comprising: extracting means for extracting a corresponding component image. 7. A work inspection for inspecting the acceptability of a work to be inspected based on an entire image of the work to be inspected and a plurality of component images indicating states of parts assembled to the work prepared in advance. Selecting a component image having the highest correlation from the plurality of component images by searching the entire image of the workpiece when a component image corresponding to the workpiece to be inspected is not prepared. And extracting an image area corresponding to the selected component image from the entire image of the workpiece to be inspected as a component image corresponding to the workpiece. A work inspection method, characterized in that a subsequent work inspection is performed using the part image obtained. 8. Inspection processing for inspecting the acceptability of a work to be inspected based on an entire image of the work to be inspected and a plurality of component images indicating states of parts assembled to the work prepared in advance. A computer-readable storage medium storing the program of the present invention, wherein the storage medium is used to search for an entire image of the work when a part image corresponding to the work to be inspected is not prepared. A selecting unit for selecting a component image having the highest correlation from among the plurality of component images, and an image area corresponding to the component image selected by the selecting unit, based on the entire image of the work to be inspected, A recording medium operated as an extracting means for extracting a part image corresponding to a work. 9. A computer-readable storage medium storing a program for a component image generation process for generating a component image indicating a state of a component mounted on a workpiece, wherein the storage medium targets a computer. A search unit that searches the entire image of the work to select a component image having the highest correlation from among a plurality of component images indicating the state of the component assembled to the work prepared in advance; A recording medium that operates as an extraction unit that extracts an image area corresponding to a part image from a whole image of the work as a part image corresponding to the work.